This invention relates to a handle bar formed as a telescopic tube, the tubes of which except for the innermost tube are provided at their one ends with external threads produced on an insert or body consisting of thermoplastic material, said body passing through apertures or cutouts in the wall of the tube, a sleeve-like threaded nut being guided on the body such that when tightening the threaded nut the portion of the body projecting into the interior of the tube is pressed against the wall of the tube to be clamped tight.
Handle bars having such a clamp device are known and are used for instance for cleaning devices such as brushes, foams or the like or for tools for applying for instance paint, in order to be able to perform cleaning or painting work located at high levels from ground or floor.
In a conventional handle bar formed as a telescopic tube, the body of the clamp device is formed annularly and provided with cylindrical external threads. It has at one of its edges a plurality of radially arranged extensions in the form of elongate arms which are subject to a bias and have a thickened portion at their free ends at the back side with which the arms pass through cutouts in the wall of the tube carrying the body. The threaded nut provided with cylindrical threading and guided on the external threads of the body forms a taper adjacent to its threads by means of which when the threaded nut is tightened down the thickened portions of the arms of the body are urged radially against the wall of the tube to be clamped tight in such a way that the tube is clamped.
Such handle bars have a substantial disadvantage to the effect that the exchanging of the annular body upon wear is rendered difficult because before the resilient arms of the body must be disengaged from the cutouts in the wall of the tube, which is possible only by means of a suitable tool. Such a tool, however, generally is not available for the purchaser of the handle bar. Furthermore, an ejection of the threaded nut from the injection-molding machine is rendered difficult by the taper adjacent to the threads of the threaded nut. Furthermore, the material demand required for the production of the annular body by the arrangement of the arms is relatively large. The same applies for the production of the threaded nut as a result of the present configuration thereof.